The formation of stripes and the enhancement of pairing in the anisotropic t-J model
Abstract
We have examined the formation of stripes and pairing in the anisotropic t - J model using exact diagonalization methods on several different cluster sizes. We have found that as the values of the long-range hopping parameters increase, the holes are found to separate while enhancing the strength of the binding, resulting in a bi-directional stripe-like configuration of charge carriers. Evidence of unidirectional stripe formation in the hole and spin correlations is found upon consideration of the phase transition between the high-temperature tetragonal and low-temperature orthorhombic phases of La214, represented by an anisotropic next-nearest neighbor hopping parameter. Upon examination of the magnetic structure factor, the values closest to (π,π) are found to increase rapidly as a function of doping, indicative of the formation of incommensurate peaks. We have determined that the formation of stripes parallel to the Cu-O-Cu bonds enhances pairing and in the bulk limit there is a finite range of doping concentration where hole pairs will form. These results are consistent with the experimental data.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARA13008V